You have three types of cones in your eye (though some women have four!)

So the eye can figure out which wavelength of light it's looking at by comparing how strongly the three types of cones are being stimulated.

When the rods and all the types of cones are working together, the eye sees all possible colors.

The two types of photoreceptors, rods and cones, are each adapted to a special type of vision.

Instead, there seem to be three different types of cones, each with a preponderance of its own characteristic pigment.

Many birds have four or more types of cones (the extra one is ultraviolet).

The human eye uses three types of cones to sense light in three bands of color.

For humans, the visible spectrum ranges approximately from 380 to 740 nm, and there are normally three types of cones.

Being color blind can change this, and there have been reports of people with four or more types of cones, giving them tetrachromatic vision.

There are different types of cones; each perceives only a single color.